Factores relacionados con las técnicas de reproducción asistida y su repercusión en el neonato

Risk of gestational diabetes mellitus in women achieving singleton pregnancy spontaneously or after ART: a systematic review and meta-analysis

BACKGROUND

Women who achieve pregnancy by ART show an increased risk of obstetric and perinatal complications compared with those with spontaneous conception (SC).

OBJECTIVE AND RATIONALE

The purpose of this systematic review and meta-analysis was to synthesize the best available evidence regarding the association between ART and gestational diabetes mellitus (GDM) in women with singleton pregnancies. The research question asked was whether the risk of GDM is higher in women achieving singleton pregnancy by ART compared with those achieving singleton pregnancy spontaneously.

SEARCH METHODS

A literature search, in MEDLINE, Scopus and Cochrane databases, covering the period 1978–2019, was performed aiming to identify studies comparing the risk of GDM in singleton pregnancies after ART versus after SC. Both matched and unmatched studies were considered eligible. Meta-analysis of weighted data was performed using the random effects model. Results were reported as risk ratio (RR) with 95% CI. Heterogeneity was quantified with the I² index.

OUTCOMES

The study reports on 63 760 women who achieved a singleton pregnancy after ART (GDM was present in 4776) and 1 870 734 women who achieved a singleton pregnancy spontaneously (GDM in 158 526). Women with singleton pregnancy achieved by ART showed a higher risk of GDM compared with those with singleton pregnancy achieved spontaneously (RR 1.53, 95% CI 1.39–1.69; I² 78.6%, n = 37, 1 893 599 women). The direction or the magnitude of the effect observed did not change in subgroup analysis based on whether the study was matched (n = 17) or unmatched (n = 20) (matched: RR 1.42, 95% CI 1.17–1.72; I² 61.5%—unmatched: RR 1.58, 95% CI 1.40–1.78; I² 84.1%) or whether it was prospective (n = 12) or retrospective (n = 25) (prospective studies: RR 1.52, 95% CI 1.27–1.83, I² 62.2%—retrospective studies: RR 1.53, 95% CI 1.36–1.72, I² 82.5%). Regarding the method of fertilization, a higher risk of GDM after ART versus SC was observed after IVF (n = 7), but not after ICSI (n = 6), (IVF: RR 1.95, 95% CI 1.56–2.44, I² 43.1%—ICSI: RR 1.42, 95% CI 0.94–2.15, I² 73.5%). Moreover, regarding the type of embryo transfer (ET), a higher risk of GDM after ART versus SC was observed after fresh (n = 14) but not after frozen (n = 3) ET (fresh ET: RR 1.38, 95% CI 1.03–1.85, I² 75.4%—frozen ET: RR 0.46, 95% CI 0.10–2.19; I² 73.1%). A higher risk of GDM was observed after ART regardless of whether the eligible studies included patients with polycystic ovary syndrome (RR 1.49, 95% CI 1.33–1.66, I² 75.0%) or not (RR 4.12, 95% CI 2.63–6.45, I² 0%), or whether this information was unclear (RR 1.46, 95% CI 1.22–1.75, I² 77.7%).

WIDER IMPLICATIONS

The present systematic review and meta-analysis, by analysing 1 893 599 women, showed a higher risk of GDM in women achieving singleton pregnancy by ART compared with those achieving singleton pregnancy spontaneously. This finding highlights the importance of early detection of GDM in women treated by ART that could lead to timely and effective interventions, prior to ART as well as during early pregnancy.

p38 MAPK regulates cavitation and tight junction function in the mouse blastocyst

Blastocyst formation is essential for implantation and maintenance of pregnancy and is dependent on the expression and coordinated function of a series of proteins involved in establishing and maintaining the trans-trophectoderm ion gradient that enables blastocyst expansion. These consist of Na/K-ATPase, adherens junctions, tight junctions (TJ) and aquaporins (AQP). While their role in supporting blastocyst formation is established, the intracellular signaling pathways that coordinate their function is unclear. The p38 MAPK pathway plays a role in regulating these proteins in other cell types and is required for embryo development at the 8–16 cell stage, but its role has not been investigated in the blastocyst.

Comparison of Growth Parameters of 5-year-old Singleton Children Born in Assisted Versus Natural Conception

Introduction: At present, about 1% of newborns are delivered through assisted reproductive technologies (ART) worldwide. This study aimed to evaluate and compare the growth parameters of children born in assisted and natural conception at 5 years of age. Materials and Methods: In a cross-sectional case control study, weight, height and head circumference of 5-year old children were assessed. The case group consisted of term, singleton babies who were products of ART in the Center for Infertility of Shahid Sadoughi University, Yazd, Iran in 2005. The control group consisted of term, first child, singleton and spontaneously conceived 5-year-old children who were referred for vaccination to primary health care center of Shahid Akbari in 2010. Results: Fifty-eight girls (47.5%) and 64 boys (52.5%) “with equal numbers in each of the 2 groups” were evaluated. Sex distribution, mean ages of fathers and mothers were not statistically significant different in both groups. Children born after ART tend to have lower birth weight, smaller birth head circumference and lower weight at 5 years of age. Having low birth weight (<2500 g), being underweight and having short stature at the age of 5 were more common in babies born through ART. Conclusion: Growth retardation is more prevalent in babies born through ART. Thus, growth assessment, parents’ knowledge about child physical development, and timely and accurate follow-up of these children are necessary for early detection of any growth disorders. Key words: ART, Growth, Height, Natural Conception, Weight