Abstract
The aim of this study was to explore the association between egg number and live birth following IVF treatment and identify the number of eggs that would optimize the IVF outcome.
Anonymized data on all IVF cycles performed in the UK between April 1991 and June 2008 were obtained from the Human Fertilisation and Embryology Authority (HFEA). The main outcome measure was the live birth rate (LBR) per cycle. A predictive model for LBR was constructed taking into account the number of eggs retrieved, the age of the woman and the year of treatment.
A total of 400 135 IVF cycles were analyzed. The median number of eggs retrieved per cycle was 9 [inter-quartile range (IQR) 6-13] and the median number of embryos created was 5 (IQR 3-8), with an overall LBR of 21.3% per fresh IVF cycle. There was a strong association between the number of eggs and LBR; LBR rose with an increasing number of eggs up to \~15, plateaued between 15 and 20 eggs and steadily declined beyond 20 eggs. For a woman aged 18-34 years having her first cycle of IVF treatment during 2006-2007, the predicted LBR for 5 eggs was 17.4%, increasing to 26.0% and 40.0% for 10 and 15 eggs, respectively. The corresponding values for women aged 35-37 years were 12.4, 19.4 and 30.6%; for women aged 38-39 years were 9.4, 15.1 and 24.4%; and for women aged 40 years and over were 5.9, 9.7 and 16.0%.
The number of eggs in IVF is a robust surrogate outcome for clinical success. We have produced a nomogram, depicting the predicted LBR with the number of eggs in different female age groups, which could be used in clinical counselling of couples undergoing IVF treatment.
By this author
The effectiveness and safety of restorative reproductive medicine (RRM) compared to assisted reproductive technology or medically unassisted conception: a systematic review
Ganci D et al., 2026 · Fertility and Sterility · Free to read
Restorative Reproductive Medicine (RRM) aims to restore fertility by diagnosing and treating the underlying causes of infertility. RRM is frequently promoted as an alternative to assisted reproductive technology (ART), despite uncertainty regarding its comparative effectiveness and safety. Where delayed childbearing and infertility are becoming more common, reliance on optimization of natural physiology alone may delay effective treatment and compromise reproductive outcomes. A systematic review of the current evidence comparing RRM to either ART or unassisted conception is, therefore, essential to inform clinical practice, guideline development, and shared decision-making for patients experiencing infertility. To assess the effectiveness and safety of RRM approaches, evaluated as a whole, rather than as individual components, compared with ART and medically unassisted conception in couples experiencing infertility. A systematic literature search of MEDLINE, Embase, CENTRAL and the Journal of Restorative Reproductive Medicine from inception to 28 November 2025. We included randomized control trials (RCTs) or nonrandomized comparative studies evaluating reproductive and safety outcomes of RRM as a unified treatment, compared with either ART or expectant management (attempted medically unassisted conception). Two reviewers independently screened titles, abstracts and full texts with disagreements resolved by a third reviewer. We retrieved 724 records, of which 16 studies underwent full-text review. No RCTs or comparative observational studies were identified. All 16 full-text studies were excluded for an ineligible study design (no control group); most were cohort studies in which all participants underwent RRM. Ten studies reported reproductive outcomes; nine of these made claims regarding the benefits or effectiveness of RRM. None of these claims were supported by the study designs used, as the lack of a comparison group precludes reliable estimation of treatment effects. Consequently, these studies cannot provide valid estimates of RRM success rates, nor permit any meaningful inference about its effectiveness relative to unassisted conception or ART. Large-scale RCTs or prospective cohort studies reporting effectiveness and safety outcomes are required to inform evidence-based fertility guidelines. There are no comparative studies to support reliable estimates of the safety and effectiveness of RRM compared with ART or medically unassisted conception for couples experiencing infertility.
Vaginal micronised progesterone for the prevention of hypertensive disorders of pregnancy: A systematic review and meta-analysis
Melo P et al., 2023 · BJOG · Free to read
Treatment with vaginal progesterone reduces the risk of miscarriage and preterm birth in selected high-risk women. The hypothesis that vaginal progesterone can reduce the risk of hypertensive disorders of pregnancy (HDP) is unexplored. To summarise the evidence on the effectiveness of vaginal progesterone to reduce the risk of HDP. Search Strategy: We searched Embase (OVID), MEDLINE (OVID), PubMed, CENTRAL and clinicaltrials.gov from inception until 20 June 2023. Selection Criteria: We included placebo-controlled randomised trials (RCTs) of vaginal progesterone for the prevention or treatment of any pregnancy complications. Data Collection and Analysis: We extracted absolute event numbers for HDP and pre-eclampsia in women receiving vaginal progesterone or placebo, and meta-analysed the data with a random effects model. We appraised the certainty of the evidence using GRADE methodology. MAIN The quantitative synthesis included 11 RCTs, of which three initiated vaginal progesterone in the first trimester, and eight in the second or third trimesters. Vaginal progesterone started in the first trimester of pregnancy lowered the risk of any HDP (risk ratio [RR] 0.71, 95% confidence interval [CI] 0.53-0.93, 2 RCTs, n = 4431 women, I(2) = 0%; moderate-certainty evidence) and pre-eclampsia (RR 0.61, 95% CI 0.41-0.92, 3 RCTs, n = 5267 women, I(2) = 0%; moderate-certainty evidence) when compared with placebo. Vaginal progesterone started in the second or third trimesters was not associated with a reduction in HDP (RR 1.19, 95% CI 0.67-2.12, 3 RCTs, n = 1602 women, I(2) = 9%; low-certainty evidence) or pre-eclampsia (RR 0.97, 95% CI 0.71-1.31, 5 RCTs, n = 4274 women, I(2) = 0%; low-certainty evidence). Our systematic review found first-trimester initiated vaginal micronised progesterone may reduce the risk of HDP and pre-eclampsia.
Evidence-based guideline: unexplained infertility
Romualdi D et al., 2023 · Hum Reprod · Free full text on PubMed Central
Guideline Group on Unexplained Infertility; Romualdi D(1), Ata B(2)(3), Bhattacharya S(4), Bosch E(5), Costello M(6)(7), Gersak K(8), Homburg R(9), Mincheva M(10), Norman RJ(7)(11), Piltonen T(12), Dos Santos-Ribeiro S(13), Scicluna D(14), Somers S(15), Sunkara SK(16), Verhoeve HR(17), Le Clef N(18).
The association between dietary patterns and risk of miscarriage: a systematic review and meta-analysis
Chung Y et al., 2023 · Fertil Steril · Free to read
The evidence on the association between diet and miscarriage risk is scant and conflicting. To summarize the evidence on the association between periconceptual diet and miscarriage risk in healthy women of reproductive age. Data Sources: Electronic databases were searched from inception to August 2022 without restriction of regions, publication types, or languages. Experimental or observational studies were considered for inclusion. The population was healthy women of reproductive age. Exposure was periconception diet. Study quality was assessed using the modified Newcastle-Ottawa Scale. Summary effect sizes (odds ratio [OR] with 95% confidence interval [CI]) were calculated for each food category. Outcomes: Miscarriage rate (as defined by primary studies). We included 20 studies (11 cohort and 9 case-control), of which 6 presented data suitable for meta-analysis (2 cohort and 4 case-control, n = 13,183 women). Our primary analyses suggest a reduction in miscarriage odds with high intake of the following food groups: fruit (OR, 0.39; 95% CI, 0.33-0.46), vegetables (OR, 0.59; 95% CI, 0.46-0.76), fruit and vegetables (OR, 0.63; 95% CI, 0.50-0.81), seafood (OR, 0.81; 95% CI, 0.71-0.92), dairy products (OR, 0.63; 95% CI, 0.54-0.73), eggs (OR, 0.81; 95% CI, 0.72-0.90), and cereal (grains) (OR, 0.67; 95% CI, 0.52-0.87). The evidence was uncertain for meat, red meat, white meat, fat and oil, and sugar substitutes. We did not find evidence of an association between adherence to predefined dietary patterns and miscarriage risk. However, a whole diet containing healthy foods as perceived by the trialists, or with a high Dietary Antioxidant Index score (OR, 0.43; 95% CI, 0.20-0.91) may be associated with a reduction in miscarriage risk. In contrast, a diet rich in processed food was demonstrated to be associated with increased miscarriage risk (OR, 1.97; 95% CI, 1.36-3.34). A diet abundant in fruit, vegetables, seafood, dairy, eggs, and grain may be associated with lower miscarriage odds. Further interventional studies are required to accurately assess the effectiveness of periconception dietary modifications on miscarriage risk. PROSPERO Registration: CRD42020218133.
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Live-Birth Rate Associated With Repeat In Vitro Fertilization Treatment Cycles
Smith ADAC et al., 2015 · JAMA · Free full text on PubMed Central
The likelihood of achieving a live birth with repeat in vitro fertilization (IVF) is unclear, yet treatment is commonly limited to 3 or 4 embryo transfers. To determine the live-birth rate per initiated ovarian stimulation IVF cycle and with repeated cycles. DESIGN, SETTING, Prospective study of 156,947 UK women who received 257,398 IVF ovarian stimulation cycles between 2003 and 2010 and were followed up until June 2012. In vitro fertilization, with a cycle defined as an episode of ovarian stimulation and all subsequent separate fresh and frozen embryo transfers. Live-birth rate per IVF cycle and the cumulative live-birth rates across all cycles in all women and by age and treatment type. Optimal, prognosis-adjusted, and conservative cumulative live-birth rates were estimated, reflecting 0%, 30%, and 100%, respectively, of women who discontinued due to poor prognosis and having a live-birth rate of 0 had they continued. Among the 156,947 women, the median age at start of treatment was 35 years (interquartile range, 32-38; range, 18-55), and the median duration of infertility for all 257,398 cycles was 4 years (interquartile range, 2-6; range, <1-29). In all women, the live-birth rate for the first cycle was 29.5% (95% CI, 29.3%-29.7%). This remained above 20% up to and including the fourth cycle. The cumulative prognosis-adjusted live-birth rate across all cycles continued to increase up to the ninth cycle, with 65.3% (95% CI, 64.8%-65.8%) of women achieving a live birth by the sixth cycle. In women younger than 40 years using their own oocytes, the live-birth rate for the first cycle was 32.3% (95% CI, 32.0%-32.5%) and remained above 20% up to and including the fourth cycle. Six cycles achieved a cumulative prognosis-adjusted live-birth rate of 68.4% (95% CI, 67.8%-68.9%). For women aged 40 to 42 years, the live-birth rate for the first cycle was 12.3% (95% CI, 11.8%-12.8%), with 6 cycles achieving a cumulative prognosis-adjusted live-birth rate of 31.5% (95% CI, 29.7%-33.3%). For women older than 42 years, all rates within each cycle were less than 4%. No age differential was observed among women using donor oocytes. Rates were lower for women with untreated male partner-related infertility compared with those with any other cause, but treatment with either intracytoplasmic sperm injection or sperm donation removed this difference. Among women in the United Kingdom undergoing IVF, the cumulative prognosis-adjusted live-birth rate after 6 cycles was 65.3%, with variations by age and treatment type. These findings support the efficacy of extending the number of IVF cycles beyond 3 or 4.
Correlation of IVF outcomes and number of oocytes retrieved: a UK retrospective longitudinal observational study of 172 341 non-donor cycles
Bahadur G et al., 2023 · BMJ Open
How do numbers of oocytes retrieved per In vitro fertilisation (IVF) cycle impact on the live birth rate (LBR) and multiple gestation pregnancy (MGP) rates? Retrospective observational longitudinal study. UK IVF clinics. Non-donor IVF patients. LBR per IVF cycle and MGP levels against number of oocytes retrieved into subgroups: 0, 1-5, 6-15, 16-25, 26-49 oocytes and 50+ oocytes. Relative risk (RR) and 95% CIs were calculated for each group against the intermediate responder with '6-15 oocytes collected'. From 172 341 attempted fresh oocyte retrieval cycles, the oocyte retrieved was: 0 in 10 148 (5.9%) cycles from 9439 patients; 1-5 oocytes in 42 574 cycles (24.7%); 6-15 oocytes in 91 797 cycles (53.3%); 16-25 oocytes in 23 794 cycles (13.8%); 26-49 oocytes in 3970 cycles (2.3%); >=50 oocytes in 58 cycles (0.033%). The LBRs for the 1-5, 6-15, 16-25 and 26-49 subgroups of oocytes retrieved were 17.2%, 32.4%, 35.3% and 18.7%, respectively. The RR (95% CI) of live birth in comparison to the intermediate group (6-15) for 1-5, 16-25 and 26-49 groups was 0.53 (0.52 to 0.54), 1.09 (1.07 to 1.11) and 0.58 (0.54 to 0.62), respectively. The corresponding MGP rates and RR were 9.2%, 11.0%, 11.4% and 11.3%, respectively and 0.83 (0.77 to 0.90), 1.04 (0.97 to 1.11) and 1.03 (0.84 to 1.26), respectively. There was only limited benefit in LBR beyond the 6-15 oocyte group going to the 16-25 oocytes group, after which there was significant decline in LBR. The MGP risk was lower in 1-5 group.
Cumulative live-birth rates after in vitro fertilization
Malizia BA et al., 2009 · N Engl J Med
Outcomes of in vitro fertilization (IVF) treatment are traditionally reported as pregnancies per IVF cycle. However, a couple's primary concern is the chance of a live birth over an entire treatment course. We estimated cumulative live-birth rates among patients undergoing their first fresh-embryo, nondonor IVF cycle between 2000 and 2005 at one large center. Couples were followed until either discontinuation of treatment or delivery of a live-born infant. Analyses were stratified according to maternal age and performed with the use of both optimistic and conservative methods. Optimistic methods assumed that patients who did not return for subsequent IVF cycles would have the same chance of a pregnancy resulting in a live birth as patients who continued treatment; conservative methods assumed no live births among patients who did not return. Among 6164 patients undergoing 14,248 cycles, the cumulative live-birth rate after 6 cycles was 72% (95% confidence interval [CI], 70 to 74) with the optimistic analysis and 51% (95% CI, 49 to 52) with the conservative analysis. Among patients who were younger than 35 years of age, the corresponding rates after six cycles were 86% (95% CI, 83 to 88) and 65% (95% CI, 64 to 67). Among patients who were 40 years of age or older, the corresponding rates were 42% (95% CI, 37 to 47) and 23% (95% CI, 21 to 25). The cumulative live-birth rate decreased with increasing age, and the age-stratified curves (< 35 vs. > or = 40 years) were significantly different from one another (P<0.001). Our results indicate that IVF may largely overcome infertility in younger women, but it does not reverse the age-dependent decline in fertility.
Observational retrospective study of US national utilisation patterns and live birth rates for various ovarian stimulation protocols for in vitro fertilisation
Kushnir VA et al., 2018 · BMJ Open · Free full text on PubMed Central
Alternative ovarian stimulation protocols for in vitro fertilisation (IVF) have grown in popularity. Yet, patient populations best suited for these protocols have not been defined. Our objective was, therefore, to determine national IVF utilisation patterns and live birth rates of various ovarian stimulation protocols. Retrospective cohort study. Academic-affiliated private fertility centre. Aggregate data published by Society for Assisted Reproductive Technology for autologous IVF cycles performed in the USA during 2014 and 2015 were analysed. IVF cycles were stratified based on ovarian stimulation protocol: 205 705 conventional stimulations, 4397 minimal stimulations, 2785 natural cycles and 514 in vitro maturation (IVM) cycles. Repeat cycles could not be determined in this analysis. Utilisation patterns and age-specific live birth rates for various ovarian stimulation protocols. With advancing female age, utilisation of conventional stimulation protocols decreased, while minimal stimulation and natural cycle IVF increased. Diminished ovarian reserve diagnoses were in all age groups less prevalent in patients undergoing conventional stimulation than with all other protocols. Live birth rates were highest with conventional stimulation at 42.4%, 33.1%, 22.1%, 11.7% and 3.9% for <35, 35-37, 38-40, 41-42 and >42 female age groups, respectively. The difference in live birth rates between conventional stimulation and other protocols widened with advancing age from 1.6-fold to 3.9-fold among women <35 years of age, reaching 4.4-fold to 6.6-fold among women >42 years of age. In comparison to conventional stimulation IVF-minimal stimulation, natural cycle IVF and IVM protocols offer lower but still acceptable live birth rates among young women. These alternative protocols are frequently used in older women and those with diminished ovarian reserve, despite their lower live birth rates. The reasons for this apparent incongruity warrant further careful exploration.