The goal of this observational study is to learn about cardiac function and remodelling and metabolomic profiles in fetuses and infants who were exposed to a threatened preterm labor (TPL) during pregnancy.

The main questions it aims to answer are:

• Evaluate the impact of threated preterm labour in cardiovascular and metabolic programming in fetal life and early infancy.
• Describe prenatal and postnatal patterns of cardiac remodelling associated to threatened preterm labour.
• Describe fetal growth patterns associated to threatened preterm labour.
• Describe metabolomic profiles in umbilical cord blood associated to cardiovascular programming in fetuses exposed to threatened preterm labour.

The study's main tasks are:

• To perform an antenatal echocardiography of the exposed cohort is performed during the admission due to TPL or preterm spontaneous rupture of membranes (SRM).
• All participants are asked to fill a diet and stress questionnaire.
• To collect cord blood at the time of delivery.
• To perform a postnatal echocardiography six months after birth.

Researchers will compare fetuses and infants who were exposed to TPL to those who were not exposed to TPL during pregnancy to see if threre are any differences in cardiac function and remodelling.

Inclusion Criteria:

• Singleton pregnancies.
• Study patients must be 18 years or older
• Good understanding of Spanish

Exclusion Criteria:

• Multiple pregnancies
• Major fetal defects or anomalies
• Underlying process that can cause a preterm labour
• Iatrogenic preterm labour

Only pregnant women are elegible for this study

Exposed cohort: women older than 18 years-old who have a singleton pregnancy and who are admitted to our unit due to TPL or preterm SRM are offered to participate in the study. Non-exposed cohort: women older than 18 years-old who have a singleton pregnancy and who attend our low-risk antenatal clinic are selected randomly and offered to participate.