Genetic variants of progesterone receptor in etiology of preterm delivery.

OBJECTIVES

Preterm delivery (PTD) accounts for around 11% of pregnancies worldwide. Unfortunately, no diagnostic indicator, specific mechanism or genetic predisposition has yet been identified. One of the hypotheses suggest local or functional progesterone decrease as a potential reason for preterm uterine contractions leading to preterm delivery. It is believed that any change in progesterone receptor DNA may be crucial for higher risk of preterm delivery due to abnormal response to prostaglandins, normally inhibited by properly built progesterone. The aim of this study was to determine whether there is an association between progesterone gene polymorphisms (PROGINS and +331G/A) and preterm birth.

MATERIAL AND METHODS

A total of 230 women were enrolled, including 115 cases of preterm deliveries (between 22 and 36 weeks of gestation) and 115 healthy mothers of full-term infants. Genomic DNA was isolated from the blood sample. Polymerase chain reaction (PCR) amplification was carried out in a final volume of 25 μL. Genotyping was assayed by PCR. Statistical analysis of the results was conducted with p < 0.05 accepted as statistically significant.

RESULTS

For both PROGINS (Alu ins/del) and +331G/A (rs10895068) polymorphisms were equally frequent in case and control group. The prevalence of PGR alleles in both groups was also comparable.

CONCLUSIONS

The results of our study showed no association between progesterone gene polymorphisms (PROGINS and +331G/A) and risk of preterm delivery. Identifying mechanisms to prolong the length of gestation, particularly in women at risk for preterm delivery, will improve both maternal and fetal outcomes.