Women with polycystic ovary syndrome (PCOS) are considered to be at increased risk of miscarriage. Since metformin has beneficial effects on the risk factors contributing to first-trimester abortion in PCOS patients, we hypothesized that metformin - owing to its metabolic, endocrine, vascular and anti-inflammatory effects - may reduce the incidence of first-trimester abortion in PCOS women.
Materials and Methods
A prospective cohort study was set up to determine the beneficial effects of metformin on PCOS patients during pregnancy. Two hundred non-diabetic PCOS patients were evaluated while undergoing assisted reproduction. One hundred and twenty patients became pregnant while taking metformin, and continued taking metformin at a dose of 1000-2000 mg daily throughout pregnancy. Eighty women who discontinued metformin use at the time of conception or during pregnancy comprised the control group.
Results
Both groups were similar with respect to all background characteristics (age, body mass index, waist/hip ratio, follicle-stimulating hormone, luteinizing hormone, estradiol and dehydroepiandrosterone sulfate levels). Rates of early pregnancy loss in the metformin group were 11.6% compared with 36.3% in the control group (p < 0.0001; odds ratio = 0.23, 95% confidence interval 0.11-0.42).
Conclusions
Administration of metformin throughout pregnancy to women with PCOS was associated with a marked and significant reduction in the rate of early pregnancy loss.
PMID 17162710 17162710 DOI 10.1080/09513590601010508 10.1080/09513590601010508
Cite this article
Khattab, S., Mohsen, I. A., Foutouh, I. A., Ramadan, A., Moaz, M., & Al-Inany, H. (2006). Metformin reduces abortion in pregnant women with polycystic ovary syndrome. Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology, 22(12), 680-684. https://doi.org/10.1080/09513590601010508
Khattab S, Mohsen IA, Foutouh IA, Ramadan A, Moaz M, Al-Inany H. Metformin reduces abortion in pregnant women with polycystic ovary syndrome. Gynecol Endocrinol. 2006;22(12):680-684. doi:10.1080/09513590601010508
Khattab, Sherif, et al. "Metformin reduces abortion in pregnant women with polycystic ovary syndrome." Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology, vol. 22, no. 12, 2006, pp. 680-684.
Euthyroid women with autoimmune thyroid disease show impairment of thyroid function during gestation and seem to suffer from a higher rate of obstetrical complications. We sought to determine whether these women suffer from a higher rate of obstetrical complications and whether levothyroxine (LT(4)) treatment exerts beneficial effects. This was a prospective study. The study was conducted in the Department of Obstetrics and Gynecology. A total of 984 pregnant women were studied from November 2002 to October 2004; 11.7% were thyroid peroxidase antibody positive (TPOAb(+)). TPOAb(+) patients group A (n = 57) was treated with LT(4), and group B (n = 58) was not treated. The 869 TPOAb(-) patients (group C) served as a normal population control group. Rates of obstetrical complications in treated and untreated groups were measured. At baseline, TPOAb(+) had higher TSH compared with TPOAb(-); TSH remained higher in group B compared with groups A and C throughout gestation. Free T(4) values were lower in group B than groups A and C after 30 wk and after parturition. Groups A and C showed a similar miscarriage rate (3.5 and 2.4%, respectively), which was lower than group B (13.8%) [P < 0.05; relative risk (RR), 1.72; 95% confidence interval (CI), 1.13-2.25; and P < 0.01; RR = 4.95; 95% CI = 2.59-9.48, respectively]. Group B displayed a 22.4% rate of premature deliveries, which was higher than group A (7%) (P < 0.05; RR = 1.66; 95% CI = 1.18-2.34) and group C (8.2%) (P < 0.01; RR = 12.18; 95% CI = 7.93-18.7). Euthyroid pregnant women who are positive for TPOAb develop impaired thyroid function, which is associated with an increased risk of miscarriage and premature deliveries. Substitutive treatment with LT(4) is able to lower the chance of miscarriage and premature delivery.
PCOSMetforminPulsatility and PCOSInsulin Resistance in Nonobese Patients
To evaluate the effects of metformin administration on spontaneous LH episodic release in a group of nonobese polycystic ovary (PCOS) patients. Controlled clinical study. PCOS patients in a clinical research environment. PATIENT(S): Twenty nonobese PCOS patients were enrolled after informed consent. INTERVENTION(S): All patients underwent hormonal evaluations and a pulsatility study (sampling every 10 minutes for 4 hours) before and at the sixth month of therapy (metformin, 500 mg, p.o. b.i.d.). Ultrasound examinations and Ferriman-Gallwey scoring were also performed. MAIN OUTCOME MEASURE(S): Measurements of plasma LH, FSH, estradiol (E(2)), androstenedione (A), 17-hydroxy-progesterone (17-OHP), and testosterone (T), glucose, insulin, and C-peptide concentrations. RESULT(S): After 6 months of metformin administration, the plasma LH, 17-OHP, A, and T levels and LH/FSH ratio were significantly reduced. Insulin sensitivity, expressed as the glucose-to-insulin ratio, was significantly improved under glucose load after 6 months of treatment. Spontaneous LH episodic release showed a significant reduction in pulse amplitude with no changes in pulse frequency. Menstrual cyclicity was restored in all amenorrheic and oligomenorrheic women. The ovarian volume and Ferriman-Gallwey scores also were significantly reduced. CONCLUSION(S): Metformin administration improves reproductive axis functioning in hyperandrogenic nonobese PCOS patients. By acting on the ovary and restoring normal ovarian activity, metformin positively modulates the reproductive axis (namely GnRH-LH episodic release).
PCOSMetforminInsulin Resistance and Diabetes RiskMetabolic Effects in PCOS
Insulin resistance is a prominent feature of polycystic ovarian syndrome (PCOS), and women with the disorder are at increased risk for the development of other diseases that have been linked to insulin resistance-namely, type 2 diabetes and cardiovascular disease. This association between insulin resistance and PCOS must guide the chronic management of the disorder, and accumulating evidence suggests that administration of insulin-sensitizing drugs to individuals at high risk for type 2 diabetes decreases the rate of conversion to overt disease. In contrast, limited evidence exists to suggest that oral contraceptive pills-the currently standard therapy for PCOS-may actually decrease insulin sensitivity and induce impaired glucose tolerance in women with PCOS. Hence, PCOS should be regarded as a general health issue and the use of insulin-sensitizing drugs such as metformin should be considered for the prevention of type 2 diabetes.
Polycystic ovary syndrome (PCOS) is a common disorder affecting women of reproductive age. Its cardinal features are hyperandrogenism, chronic anovulation, and infertility. Some of the most important pathogenic associations of PCOS are insulin resistance and compensatory hyperinsulinemia (1, 2, 3). The hyperinsulinemia in turn stimulates ovarian androgen production. Several clinical studies have demonstrated that a reduction in the insulin level results in decreased ovarian androgen production (4, 5, 6).
Metformin is a biguanide used extensively in type 2 diabetes. It inhibits hepatic gluconeogenesis and increases peripheral insulin sensitivity and glucose uptake but does not cause hypoglycemia (6, 7, 8). The correction of the hyperinsulinemia by metformin in PCOS patients is accompanied by normalization of the elevated serum LH and ovarian androgen levels, leading to resumption of spontaneous ovulatory cycles, or responsiveness to ovulation induction by clomiphene citrate (CC) (1, 4, 5, 6, 8, 9). Clinical use of this agent for ovulation induction in CC-resistant PCOS patients has increased with little knowledge of the possible effect on early embryo development. We sought to assess whether metformin was embryotoxic using a mouse embryo model.
During controlled clinical trials, plasma metformin levels do not exceed 5 μg/mL, even at maximum doses (10). Metformin hydrochloride (N, N-dimethylimidodicarbonimidic diamide hydrochloride; Sigma, St. Louis, MO) was dissolved in human tubal fluid (HTF) media (Irvine Scientific, Santa Ana, CA) to give working concentrations of 5, 25, and 100 μg. The culture dishes containing 1 mL of media at each concentration were incubated for overnight equilibration at 37°C and 5% CO2.
Thawed two-cell mouse embryos (Embryotech, Wilmington, MA) were pooled and randomly distributed into the culture dishes containing the various concentrations of metformin. The control consisted of HTF media alone (group 1). Groups 2, 3, and 4 were supplemented with metformin (5, 25, and 100 μg/mL). There were 40 embryos in each group. The embryos were incubated in an atmosphere of 5% CO2 at 37°C for 72 hours. The blastocyst development rate (BDR) was then calculated by dividing the number of embryos reaching the blastocyst stage by the total number of embryos cultured.
The relationship between BDR and concentration was assessed with repeated measures logistic regression using generalized estimated equation (GEE) methodology with a compound symmetry correlation structure. The sample size was sufficient to detect whether a specific concentration reduced the odds of development by a factor of 2.5. Statistical significance was assessed using two-tailed P<.05. Statistical computations were performed with SAS version 8.1 (SAS Institute Inc, Cary, NC). . .