Metformin hydrochloride and recurrent miscarriage in a woman with polycystic ovary syndrome

Insulin resistance in women with recurrent miscarriage: a systematic review and meta-analysis

PURPOSE

This review aimed to investigate the association of insulin resistance (IR) in women with recurrent pregnancy loss compared to women with normal pregnancy history.

METHODS

PubMed, EMBASE, the Web of Science and Google Scholar databases were accessed to collect published observational studies that compared IR of recurrent pregnancy loss women with healthy women until the 6^th of October 2022. Outcomes assessed in this review and meta-analysis included fasting blood glucose, fasting plasma insulin, homeostasis model assessment for IR, glucose to insulin ratio. Mean differences, odds ratios with 95% confidence interval were pooled using the fixed or random effect models. Sensitivity analyses were performed to validate the robustness of the results. Review Manager version 5.4.1 and Stata version 8.0 were used.

RESULTS

A total of nineteen studies involving 4453 individuals were included. Recurrent pregnancy loss patients presented significantly higher fasting blood glucose, fasting plasma insulin, homeostasis model assessment for IR, and lower glucose to insulin ratios. Additionally, recurrent pregnancy loss patients had higher rates of IR as defined by abnormal fasting plasma insulin, homeostasis model assessment for IR, and glucose to insulin ratio. Sensitivity analyses validated the robustness of the results.

CONCLUSION

In the current review, we show that recurrent pregnancy loss is associated with a higher degree of IR and highlight the importance of screening and treatment of IR.

Polycystic Ovarian Syndrome (PCOS): Does the Challenge End at Conception?

Polycystic ovary syndrome (PCOS) is a prevalent condition that not only has the potential to impede conception but also represents the most common endocrine dysfunction in fertile women. It is considered a heterogeneous and multifaceted disorder, with multiple reproductive and metabolic phenotypes which differently affect the early- and long-term syndrome's risks. Undoubtedly, the impact of PCOS on infertility has attracted most of the attention of healthcare providers and investigators. However, there is growing evidence that even after conception is achieved, PCOS predisposes the parturient to several adverse pregnancy outcomes including a high risk of pregnancy-induced hypertension, spontaneous abortion, gestational diabetes, preeclampsia, and preterm birth, which increase the risks of stillbirth and neonatal death. Fetal growth abnormalities may also be more common, but the relationship is less well defined. This narrative review aims to summarize current knowledge regarding these conditions as they interplay with PCOS and concludes that although there appears to be an increase in these complications during the pregnancy of women with PCOS, there is a need for further research to clarify the possible confounding impact of obesity. Implications for clinical practice and future research are outlined.

Circulating levels of matrix proteases and their inhibitors in pregnant women with and without a history of recurrent pregnancy loss

BACKGROUND

We have recently shown that serum relaxin-2 levels are attenuated in women with a history of recurrent pregnancy loss (RPL). We sought to determine whether a history of RPL is also associated with changes in serum matrix metalloproteases (MMPs) and tissue inhibitors of matrix metalloproteases (TIMP) -1 and -2.

METHODS

We obtained serum from 20 pregnant women with a history of RPL and 20 age-matched pregnant women with no history of RPL (NRPL) at 6-8, 10-12, 20, and 34 weeks gestation, and from cord blood. We quantified total serum concentrations of MMP-1, MMP-3, MMP-9 and TIMP-1 and TIMP-2 by ELISA. We determined whether these serum marker levels were associated with a history of RPL and delivery before 37 weeks gestation.

RESULTS

There was no difference in the rates of miscarriage, preterm birth or prelabour rupture of fetal membranes between RPL and NRPL. However babies born to RPL were lighter than those born to NRPL. Serum MMP-1, 9, and TIMP-1 did not differ between RPL and NRPL but MMP-3 was higher in RPL vs. NRPL at 6-8 weeks (P < 0.05). Serum TIMP-2 levels were higher in RPL women at all gestations (P < 0.01). The ratio of RLX-2 (reported previously) to TIMP-2 at 10-12 weeks gestation was more strongly associated with a history of RPL than either peptide separately - area under the ROC curves for RLX-2 0.79 (95% CI 0.57 to 0.92), TIMP-2 0.83 (95% CI 0.63 to 0.95), and for RLX-2:TIMP-2 ratio 0.92 (95% CI 0.74 to 0.99).

CONCLUSIONS

Women with a history of RPL demonstrate increased serum TIMP-2 and reduced RLX-2 during a subsequent viable pregnancy. Determination of both markers in early pregnancy enhances the discrimination of women with a history of RPL. These observations suggest roles for these two peptides in early implantation and placental development. Whether these may prove to be reliable early predictive markers for subsequent pregnancy loss in the index pregnancy is unknown and will require further studies.

Evidence-based and potential benefits of metformin in the polycystic ovary syndrome: a comprehensive review

Metformin is an insulin sensitizer widely used for the treatment of patients affected by type 2 diabetes mellitus. Because many women with polycystic ovary syndrome (PCOS) are insulin resistant, metformin was introduced in clinical practice to treat these patients also. Moreover, metformin's effect has other targets beside its insulin-sensitizing action. The present review was aimed at describing all evidence-based and potential uses of metformin in PCOS patients. In particular, we will analyze the uses of metformin not only for the treatment of all PCOS-related disturbances such as menstrual disorders, anovulatory infertility, increased abortion, or complicated pregnancy risk, hyperandrogenism, endometrial, metabolic and cardiovascular abnormalities, but also for the prevention of the syndrome.

Effect of preconceptional metformin on abortion risk in polycystic ovary syndrome: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To evaluate the effect of pregestational metformin administration on abortion risk in polycystic ovary syndrome (PCOS) patients.

DESIGN

Systematic review and meta-analysis.

SETTING

Academic Department of Obstetrics and Gynecology in Italy.

PATIENT(S)

Women affected by PCOS receiving pregestational metformin.

INTERVENTION(S)

Systematic review of randomized controlled trials (RCTs) published up to June 2008 and subsequent meta-analysis.

MAIN OUTCOME MEASURE(S)

Abortion rate.

RESULT(S)

Seventeen RCTs were included in the final analysis. Overall, no effect of the metformin administration was detected on the abortion risk. No statistically significant effect of metformin on the abortion risk was observed in any comparison when subgrouping the RCTs according to received treatment.

CONCLUSION(S)

Metformin has no effect on the abortion risk in PCOS patients when administered before pregnancy.

Case series of rosiglitazone used during the first trimester of pregnancy

Prior to 2007, use of the insulin sensitizer metformin was widely advocated in patients with polycystic ovarian syndrome (PCOS) both to promote ovulation and decrease the incidence of PCOS-associated obstetrical complications. However, the gastrointestinal disturbances associated with metformin led many to discontinue its use. Rosiglitazone is an insulin sensitizer that, because of minimal associated gastrointestinal disturbance, was used as an alternative to metformin in PCOS patients. From 2003 to 2005, 8 women with PCOS unable to tolerate metformin used rosiglitazone for ovulation induction and during their first 12 weeks of gestation. All delivered healthy babies at term, without obstetric complications or congenital anomalies. However, given recent evidence that disputes the reproductive benefits of insulin sensitization for PCOS and that raises safety concerns of rosiglitazone, we are no longer using it for PCOS treatment.

Prevention of gestational diabetes by metformin plus diet in patients with polycystic ovary syndrome

OBJECTIVE

To prospectively assess whether metformin diet safely provides primary and secondary prevention of gestational diabetes (GD).

DESIGN

Assess development of GD on metformin diet.

SETTING

Outpatient clinical research center.

PATIENT(S)

One hundred forty-two nondiabetic women with polycystic ovary syndrome (PCOS) who had at least one live-birth (LB) pregnancy on metformin diet (172 pregnancies, 180 LBs).

INTERVENTION(S)

Women were given 26% protein, 44% carbohydrate diets, without calorie restriction during pregnancy. Metformin (2-2.55 g/d) was given preconception, through pregnancy.

MAIN OUTCOME MEASURE(S)

Development of GD.

RESULT(S)

On metformin, GD developed in 12 (7%) of 172 LB pregnancies. Forty-seven women had at least one previous LB pregnancy (n = 64) without metformin, with GD developing in 19 (30%). Subsequently, on metformin, these 47 women had 50 LB pregnancies, developing GD in 6 (12%), which was a statistically significant difference. Of 15 women who had previous GD without metformin, GD developed in 5 (31%) of 16 subsequent pregnancies on metformin. Of 32 women who were previously free of GD without metformin, GD developed in 1 (3%) of 34 subsequent pregnancies on metformin. Previous GD without metformin was the only statistically significant explanatory variable for current GD on metformin.

CONCLUSION(S)

Metformin diet during pregnancy in women with PCOS facilitates primary and secondary prevention of GD.

Relationship between abnormal glucose tolerance test and history of previous recurrent miscarriages, and beneficial effect of metformin in these patients: a prospective clinical study

OBJECTIVE

To determine the incidence of an abnormal glucose tolerance test in patients with recurrent spontaneous abortion and whether metformin would safely reduce the rate of first trimester spontaneous abortions in patients without polycystic ovary syndrome (PCOS) as well as with PCOS and an abnormal glucose tolerance test.

DESIGN

Prospective control clinical trial.

SETTING

Shiraz University-affiliated hospital.

PATIENT(S)

Patients with a history of recurrent spontaneous abortion and women with a history of normal full term pregnancy.

INTERVENTION(S)

The incidence of abnormal carbohydrate metabolism was determined. Metformin and placebo were given to women with an abnormal glucose tolerance test and who had recurrent spontaneous abortions.

MAIN OUTCOME MEASURE(S)

Continuation of pregnancy beyond the first trimester in all groups and presence or absence of teratogenicity in the delivered baby after metformin therapy.

RESULT(S)

Twenty-nine of the patients in the group with recurrent spontaneous abortion were found to have an abnormal glucose tolerance test result compared with just four (5.4%) patients in the normal pregnancy group. The abortion rate was significantly reduced after metformin therapy in patients without PCOS in comparison to the placebo group (15% vs. 55%).

CONCLUSION(S)

This study indicates an important link between an abnormal glucose tolerance test and a history of recurrent abortion. It was also found that metformin therapy improves the chances of a successful pregnancy in patients with an abnormal glucose tolerance test.