Assisted Reproduction · Safety and Risks
Abstract
To evaluate the odds of developing adverse maternal and perinatal outcomes in primiparous singleton pregnancies conceived with assisted reproductive technology (ART) compared with pregnancies conceived without ART.
A retrospective population-based cohort study using data from the British Columbia Perinatal Data Registry. The population included primiparous women with singleton live or stillbirths delivering at or after 20 weeks' gestation between April 1st 2008-March 31st, 2021. Women who conceived with ART were compared with those who conceived without ART. The main outcome measures were gestational diabetes, hypertensive disorders of pregnancy, preterm birth, low birth weight, neonatal intensive care unit admission, stillbirth, and 5-minute Apgar score. Adjusted odds ratios were calculated.
The study population included 191,059 primiparous women: 183,819 conceived without ART, 7,240 conceived using ART. After controlling for age, body mass index, pre-gestational diabetes, and smoking status, singleton pregnancies conceived by ART had significantly higher odds of gestational diabetes (OR 1.18, 95 % confidence interval [CI] 1.10-1.26) and hypertensive disorders of pregnancy (OR 1.39, 95 % CI 1.29-1.51). There were also significantly increased odds of preterm birth (OR 1.35, 95 % CI 1.25-1.46), low birth weight (OR 1.35, 95 % CI 1.23-1.49), and neonatal intensive care unit admission (OR 1.21, 95 % CI 1.11-1.32). There was not a statistically significant difference in the odds of stillbirth (OR 1.06, 95 % CI 0.72-1.57) or 5-minute Apgar score < 7 (OR 1.10, 95 % CI 0.97-1.26).
There is an increased odds of developing several adverse maternal or neonatal outcomes in primiparous singleton pregnancies conceived by ART including gestational diabetes, hypertensive disorders of pregnancy, preterm birth, low birth weight, and increased incidence of neonatal intensive care unit admissions.
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By this author
Mid-Cycle Pain in Endometriosis: Clinical Correlations and Potential Etiological Factors
Rojas HE et al., 2026 · Journal of women's health (2002)
To characterize differences between individuals with and without mid-cycle pain in a registry cohort with endometriosis. Prospective analysis of data from the Endometriosis Pelvic Pain Interdisciplinary Cohort Data Registry (Clinicaltrials.gov #NCT02911090) at a tertiary referral center in Western Canada. Three hundred forty-five individuals aged 18-49 years who: (1) had at least one episode of menstrual bleeding in the last 3 months, (2) attended a baseline initial visit, and (3) subsequently had surgery with histological confirmation of endometriosis between January 2018 and December 2023. Exclusion criteria included (1) previous hysterectomy; (2) hormonal suppressive therapy use in the last 3 months; and (3) missing data on mid-cycle pain, history of hormonal therapy use, or menstrual cycle regularity. N/A. Mid-cycle pain in the last month versus No mid-cycle pain in the last month. Of the 345 participants, 67% (n = 232) reported mid-cycle pain in the last month. Mid-cycle pain in the last month was significantly associated with higher mean Central Sensitization Inventory score (48 ± 17 versus 36 ± 16, p < 0.001) and more months of prior hormonal suppressive therapy use (58 [14-120] versus 26 [0-109], p = 0.012). Abnormal anatomy at the time of surgery (e.g., endometrioma, ovarian adhesions) was not associated with mid-cycle pain in the last month. In this endometriosis cohort at a tertiary referral center, most participants reported mid-cycle pain in the last month, which was associated with central sensitization but was not clearly related to endometriosis anatomical distortion.
Validating ovulation prediction and confirmation with the Mira monitor: blinded ultrasound and serum hormone comparison
Bouchard TP et al., 2026 · Reproductive biomedicine online · Free to read
Do quantitative urinary hormone measurements on the Mira monitor predict and confirm ovulation accurately compared with ultrasound in women with regular menstrual cycles? Do Mira urine hormones correlate with serum hormones? This was a prospective, single-centre, blinded diagnostic accuracy study with 52 women aged 19-44 years with regular cycles (24-38 days) who tracked 153 cycles over 18 months. Daily first-morning urine was tested with the Mira monitor for follicle stimulating hormone (FSH), oestrone-3-glucuronide (E13G), luteinizing hormone (LH) and pregnanediol glucuronide (PDG). Serial transvaginal ultrasounds (890 scans) confirmed the day of ovulation. Serum hormones were measured twice per cycle. The 121 ovulatory cycles from 49 participants with sufficient index test and reference standard data were included in the final analysis. The Mira LH peak day strongly predicted ultrasound-confirmed ovulation (R² = 0.96, P < 0.001; intraclass correlation coefficient = 0.971), with 96% of ovulations occurring within ±1 day. The Mira PDG increase was also strongly associated with ultrasound-confirmed day of ovulation (R² = 0.87, P < 0.001). First-morning urine hormones were significantly associated with serum hormones when collected within 90 min (LH: R² = 0.92; E13G: R² = 0.73; R² = 0.61; R² = 0.75). Anovulatory cycles were identified in 11% of regularly cycling participants. Quantitative urinary hormone monitoring with the Mira monitor provides accurate prediction and confirmation of ovulation, with strong urine-serum associations supporting reduced reliance on serial serum draws in select patients. These findings support clinical adoption of quantitative urinary fertility monitoring.
Impact of the coronavirus disease-2019 (COVID-19) pandemic on reproductive outcomes in patients with recurrent pregnancy loss
Balachandran S et al., 2026 · Journal of obstetrics and gynaecology Canada : JOGC = Journal d'obstetrique et gynecologie du Canada : JOGC
To assess the impact of the COVID-19 pandemic on reproductive outcomes in patients with recurrent pregnancy loss (RPL) and the influence of material and social deprivation on these outcomes. This retrospective cohort study included RPL patients seen at a specialized clinic between March 1, 2018, and February 28, 2022. Patients were categorized into two groups based on care period: pre-pandemic (March 1, 2018-February 29, 2020) and pandemic (March 1, 2020-February 28, 2022). Cumulative probabilities of birth were estimated using the cumulative incidence function within a competing risk framework, treating pregnancy loss as a competing event. Fine and Gray regression models calculated sub-distribution hazard ratio (sHR) of birth. 544 patients were included in the study, with 255 in the pre-pandemic group and 289 in the pandemic group. Individuals in the pandemic group were less likely to achieve pregnancy than those in the pre-pandemic group (relative risk = 0.50, 95% confidence interval [CI] 0.39 - 0.66). Among those who conceived, the cumulative probability of live birth was 0.77 in both groups. Relative to individuals residing in high-social deprivation neighborhoods, those living in moderately deprived areas had higher sub-distribution hazards of live birth (adjusted sHR = 1.97, 95% CI 1.25 - 3.10; P = 0.003). Within specialized RPL care and a universal maternity care system, pregnancy rates were lower during the first two years of the COVID-19 pandemic. However, among those who conceived, the probability of achieving a live birth remained similar between the pre-pandemic and pandemic periods.
Using corpus luteum formation with dominant follicle collapse to improve the criteria for identifying ovulation
Bouchard TP et al., 2026 · Reproductive biomedicine online · Free to read
Does formation of the corpus luteum help to identify the day of ovulation on ultrasound when follicular collapse is missed, and how reliable are sonographers versus a review panel in identifying the day of ovulation on ultrasound? Sonographers in a clinic in Canada performed serial endovaginal ultrasound scans (six to eight per cycle) to identify the day of ovulation in regularly cycling women (n = 40) who were followed for one to five cycles (n = 85). The day of ovulation was identified by: (i) identification of the dominant follicle; (ii) disappearance of the dominant follicle; and (iii) identification and dating of the corpus luteum. The main outcome measures were inter-rater reliability between two sonographers, and Bland-Altman agreement between the supervising sonographer and a panel that reviewed each scan to identify the day of ovulation. Of the 85 menstrual cycles reviewed, two cycles did not have sufficient data to date ovulation, one cycle showed an incidental dermoid cyst, and 11 cycles showed anovulatory patterns. This left a total of 71 cycles (84%) for which intra-rater reliability between two sonographers for identifying the day of ovulation was high (intraclass correlation coefficient = 0.99, P < 0.0001), and Bland-Altman agreement showed no significant difference in the estimated day of ovulation between the supervising sonographer and the panel (t = -0.28, P = 0.78). Corpus luteum criteria were necessary to help identify the day of ovulation in 14 of 71 cycles (20%). The estimated day of ovulation can be determined reliably on ultrasound by trained sonographers using collapse of the dominant follicle and formation of the corpus luteum based on six to eight scans per cycle.
Related research
Assisted reproductive technology and the risk of pregnancy-related complications and adverse pregnancy outcomes in singleton pregnancies: a meta-analysis of cohort studies
Qin J et al., 2016 · Fertility and sterility
To determine whether there are any increases in pregnancy-related complications and adverse pregnancy outcomes in singleton pregnancies after assisted reproductive technology (ART) compared with those conceived naturally. Meta-analysis. University-affiliated teaching hospital. PATIENT(S): Singleton pregnancies conceived with ART and naturally. INTERVENTION(S): PubMed, Google Scholar, Cochrane Libraries and Chinese database were searched through March 2015 to identify studies that met pre-stated inclusion criteria. Either a fixed- or a random-effects model was used to calculate the overall combined risk estimates. Subgroup analysis was performed to explore potential heterogeneity moderators. MAIN OUTCOME MEASURE(S): Pregnancy-related complications and adverse pregnancy outcomes. RESULT(S): Fifty cohort studies comprising 161,370 ART and 2,280,241 spontaneously conceived singleton pregnancies were identified. The ART singleton pregnancies had a significantly increased risk of pregnancy-induced hypertension (relative risk [RR] 1.30, 95% confidence interval [CI] 1.04-1.62; I(2) = 79%), gestational diabetes mellitus (RR 1.31, 95% CI 1.13-1.53; I(2) = 6%), placenta previa (RR 3.71, 95% CI 2.67-5.16; I(2) = 72%), placental abruption (RR 1.83, 95% CI 1.49-2.24; I(2) = 22%), antepartum hemorrhage (RR 2.11, 95% CI 1.86-2.38; I(2) = 47%), postpartum hemorrhage (RR 1.29, 95% CI 1.06-1.57; I(2) = 65%), polyhydramnios (RR 1.74, 95% CI 1.24-2.45; I(2) = 0%), oligohydramnios (RR 2.14, 95% CI 1.53-3.01; I(2) = 0%), cesarean sections (RR 1.58, 95% CI 1.48-1.70; I(2) = 92%), preterm birth (RR 1.71, 95% CI 1.59-1.83; I(2)=80%), very preterm birth (RR 2.12, 95% CI 1.73-2.59; I(2) = 90%), low birth weight (RR 1.61, 95% CI 1.49-1.75; I(2) = 80%), very low birth weight (RR 2.12, 95% CI 1.84-2.43; I(2) = 67%), small for gestational age (RR 1.35, 95% CI 1.20-1.52; I(2) = 82%), perinatal mortality (RR 1.64, 95% CI 1.41-1.90; I(2)=45%), and congenital malformation (RR 1.37, 95% CI 1.29-1.45; I(2)=41%). Relevant heterogeneity moderators have been identified by subgroup analysis. Sensitivity analysis yielded consistent results. No evidence of publication bias was observed. CONCLUSION(S): The ART singleton pregnancies are associated with higher risks of adverse obstetric outcomes. Obstetricians should manage these pregnancies as high risk.
Assisted reproductive technology and hypertensive disorders of pregnancy: systematic review and meta-analyses
Chih HJ et al., 2021 · BMC Pregnancy and Childbirth · Free full text on PubMed Central
Hypertensive disorders of pregnancy (HDP) is one of the most common pregnancy complications and causes of maternal morbidity and mortality. Assisted reproductive technology (ART) has been associated with adverse pregnancy outcomes, including HDP. However, the impact of multiple pregnancies, oocyte donation, as well as fresh and frozen embryo transfer needs to be further studied. We conducted a systematic review and meta-analyses to evaluate the association between ART and HDP or preeclampsia relative to spontaneous conception (SC). We identified studies from EMBASE, MEDLINE, and Cochrane Library (up to April 8, 2020) and manually using structured search strategies. Cohort studies that included pregnancies after in vitro fertilization (IVF) with or without intracytoplasmic sperm fertilization (ICSI) relative to SC with HDP or preeclampsia as the outcome of interest were included. The control group was women who conceived spontaneously without ART or fertility medications. The pooled results were reported in odds ratios (OR) with 95% confidence intervals based on random effects models. Numbers needed to harm (NNH) were calculated based on absolute risk differences between exposure and control groups. Eighty-five studies were included after a screening of 1879 abstracts and 283 full text articles. Compared to SC, IVF/ICSI singleton pregnancies (OR 1.70; 95% CI 1.60-1.80; I2 = 80%) and multiple pregnancies (OR 1.34; 95% CI 1.20-1.50; I2 = 76%) were both associated with higher odds of HDP. Singleton pregnancies with oocyte donation had the highest odds of HDP out of all groups analyzed (OR 4.42; 95% CI 3.00-6.51; I2 = 83%). Frozen embryo transfer resulted in higher odds of HDP (OR 1.74; 95% CI 1.58-1.92; I2 = 55%) than fresh embryo transfer (OR 1.43; 95% CI 1.33-1.53; I2 = 72%). The associations between IVF/ICSI pregnancies and SC were similar for preeclampsia. Most interventions had an NNH of 40 to 100, while singleton and multiple oocyte donation pregnancies had particularly low NNH for HDP (16 and 10, respectively). Our meta-analysis confirmed that IVF/ICSI pregnancies are at higher odds of HDP and preeclampsia than SC, irrespective of the plurality. The odds were especially high in frozen embryo transfer and oocyte donation pregnancies.
In-Hospital Complications in Pregnancies Conceived by Assisted Reproductive Technology
Wu P et al., 2022 · Journal of the American Heart Association · Free full text on PubMed Central
Background Assisted reproductive technology (ART) has emerged as a common treatment option for infertility, a problem that affects an estimated 48 million couples worldwide. Advancing maternal age with increasing prepregnancy cardiovascular risk factors, such as chronic hypertension, obesity, and diabetes, has raised concerns about pregnancy complications associated with ART. However, in-hospital complications following pregnancies conceived by ART are poorly described. Methods and Results To assess the patient characteristics, obstetric outcomes, vascular complications and temporal trends of pregnancies conceived by ART, we analyzed hospital deliveries conceived with or without ART between January 1, 2008, and December 31, 2016, from the United States National Inpatient Sample database. We included 106 248 deliveries conceived with ART and 34 167 246 deliveries conceived without ART. Women who conceived with ART were older (35 versus 28 years; P<0.0001) and had more comorbidities. ART-conceived pregnancies were independently associated with vascular complications (acute kidney injury: adjusted odds ratio [aOR], 2.52; 95% CI 1.99-3.19; and arrhythmia: aOR, 1.65; 95% CI, 1.46-1.86), and adverse obstetric outcomes (placental abruption: aOR, 1.57; 95% CI, 1.41-1.74; cesarean delivery: aOR, 1.38; 95% CI, 1.33-1.43; and preterm birth: aOR, 1.26; 95% CI, 1.20-1.32), including in subgroups without cardiovascular disease risk factors or without multifetal pregnancies. Higher hospital charges ($18 705 versus $11 983; P<0.0001) were incurred compared with women who conceived without ART. Conclusions Pregnancies conceived by ART have higher risks of adverse obstetric outcomes and vascular complications compared with spontaneous conception. Clinicians should have detailed discussions on the associated complications of ART in women during prepregnancy counseling.
Why do singletons conceived after assisted reproduction technology have adverse perinatal outcome? Systematic review and meta-analysis
Pinborg A et al., 2013 · Human reproduction update
Assisted reproduction technology (ART) is used worldwide, at increasing rates, and data show that some adverse outcomes occur more frequently than following spontaneous conception (SC). Possible explanatory factors for the well-known adverse perinatal outcome in ART singletons were evaluated. PubMed and Cochrane databases from 1982 to 2012 were searched. Studies using donor or frozen oocytes were excluded, as well as those with no control group or including <100 children. The main outcome measure was preterm birth (PTB defined as delivery <37 weeks of gestation), and a random effects model was used for meta-analyses of PTB. Other outcomes were very PTB, low-birthweight (LBW), very LBW, small for gestational age and perinatal mortality. The search returned 1255 articles and 65 of these met the inclusion criteria. The following were identified as predictors for PTB in singletons: SC in couples with time to pregnancy (TTP) > 1 year versus SC singletons in couples with TTP ≤ 1 year [adjusted odds ratio (AOR) 1.35, 95% confidence interval (CI) 1.22, 1.50]; IVF/ICSI versus SC singletons from subfertile couples (TTP > 1 year; AOR 1.55, 95% CI 1.30, 1.85); conception after ovulation induction and/or intrauterine insemination versus SC singletons where TTP ≤ 1 year (AOR 1.45, 95% CI 1.21, 1.74); IVF/ICSI singletons versus their non-ART singleton siblings (AOR 1.27, 95% CI 1.08, 1.49). The risk of PTB in singletons with a 'vanishing co-twin' versus from a single gestation was AOR of 1.73 (95% CI 1.54, 1.94) in the narrative data. ICSI versus IVF (AOR 0.80, 95% CI 0.69-0.93), and frozen embryo transfer versus fresh embryo transfer (AOR 0.85, 95% CI 0.76, 0.94) were associated with a lower risk of PTB. Subfertility is a major risk factor for adverse perinatal outcome in ART singletons, however, even in the same mother an ART singleton has a poorer outcome than the non-ART sibling; hence, factors related to the hormone stimulation and/or IVF methods per se also may play a part. Further research is required into mechanisms of epigenetic modification in human embryos and the effects of cryopreservation on this, whether milder ovarian stimulation regimens can improve embryo quality and endometrial conditions, and whether longer culture times for embryos has a negative influence on the perinatal outcome.