No difference in singleton birth weight according to the type of culture medium and according to the duration of in vitro culture

Study question: Does the type of medium for in vitro culture and the duration
of culture influence singleton birth weight after IVF/ICSI treatment?
Summary answer: The present study did not show any difference in mean
singleton birth weight according to four different culture media. Day 5 blastocyst
transfer resulted in a similar mean singleton birth weight as compared to
day 3 embryo transfer.
What is known already: Previous studies have indicated that in vitro culture of
human embryos may affect birth weight of live born singletons. Both the culture
medium and the duration of culture might be implicated. However, few studies
have confirmed an effect of culture medium and duration on birth weight and
reports are conflicting.
Study design, size, duration: A large retrospective analysis was conducted,
including all singleton live births after transfer of fresh day 3 or day 5 embryos
resulting from IVF and ICSI cycles performed between March 2004 and
February 2012.
Participants/materials, setting, methods: A total of 3154 singleton live births
resulting from singleton pregnancies were considered for the analysis. Four
different sequential embryo culture media were used: Cook (n = 158), Medicult
(n = 1388), Sage (n = 898) and Vitrolife (n = 710). Maternal age, maternal
and paternal BMI, maternal smoking, maternal parity, main cause of infertility,
method of fertilization (IVF or ICSI), time in culture and number of embryos
transferred were documented. Embryo transfers were performed either on day 3
(n = 1855) or on day 5 (n = 1299). Singleton birth weight was the primary
outcome parameter. Other outcome parameters included gestational age, mode
of delivery, and gender of the newborn.
Main results and the role of chance: No significant differences in mean singleton
birth weight (±SE) were observed among the four culture media: Cook
3259g (±43), Medicult 3222g (±15), Sage 3281g (±19), and Vitrolife 3251g
(±21) (P = 0.107). The mean singleton birth weight was not different between
day 3 embryo transfers (3241 ± 13 g) and day 5 blastocyst transfers (3257 ± 16 g;
P = 0.425). Multiple regression analysis controlling for maternal, paternal,
treatment and newborn potential confounders confirmed the non-significant
differences in mean singleton birth weight among the four culture media. Likewise,
the adjusted mean singleton birth weight was not different according to the
culture duration (P = 0.805).
Limitations, reason for caution: Our study is limited by its retrospective
design and the fact that the four different sequential culture systems were used
in different time periods. However, no other significant changes were introduced
in the laboratory procedures during the whole study period. One of the four
culture media groups represents a rather small group. Pregnancy-associated
factors possibly influencing birth weight (such as diabetes, hypertension, preeclampsia)
were not included in the analysis.
Wider implications of the findings: The present large retrospective study
does not confirm earlier concern that both the type of culture medium (smaller
studies) and the duration of embryo culture could influence singleton birth
weight. However, a continuous surveillance of human embryo culture procedures
(medium type, culture duration and other culture conditions) seems
warranted.
Study funding/competing interest(s): Funding by hospital/clinic(s), UZ Brussel.
Trial registration number: Not applicable.

Jaar van publicatie:2014

Trefwoorden:in-vitro culture, birth weight, singleton

Toegankelijkheid:Closed