Uterine Contractions Under Blue Light

The objective in the current study is to test the hypothesis that nocturnal uterine contractions in preterm women can be suppressed by brief ocular exposure to blue light.The Olcese lab at Florida State University identified a novel interaction between the myometrial melatonin receptors and OT receptors in human myometrial cells (Sharkey et al. 2009), which may ultimately help to resolve certain issues surrounding idiopathic preterm labor. Their results consistently indicate that melatonin at physiological concentration sensitizes human myometrial smooth muscle cells to the contractile effects of OT (Sharkey et al. 2010).

Study participants will be pregnant women (gestational weeks 24 to 31+6 days) who present with preterm contractions. In the triage room, the study participant will be connected to the external tocometer from at least 19:00h (7 PM) to the following morning at 07:00h. Room lighting will be kept dim. Participants meeting inclusion criteria will be randomly allocated to blue light or red light. Baseline contractions will be measured. The allocated light mask will be applied for 2 intervals of 60 minutes each.There will be a 60 minute rest period after every 60 minute intervention period for comparison. Other than the application of the light mask, all routine standards of care deemed warranted by the obstetric provider for proper treatment of preterm labor will be followed. (ie antenatal steroids, tocolytics).

Study group assignments will be placed in an opaque envelope which will be kept in the designated research area on Labor and Delivery. After informed consent is obtained, the coordinator will take one of the envelopes to determine the study group. The coordinator will not communicate with the care provide or the investigator regarding study group assignment.

Ocular light will be applied via a mask. The participants allocated to the experimental group will receive blue light

Ocular light will be applied via a mask. The participants allocated to the control group will receive red light

A light mask to which small light emitting diode(LED) lights emitting a blue or red color light will be used to deliver ocular light

Inclusion Criteria: Pregnant Gestational age: 24 to 31 (+6 days) week of pregnancy Uterine contractions First episode of preterm labor Exclusion Criteria: Visual impairment (legally blind) Multiple pregnancy Current progesterone treatment Preeclampsia Renal disease Current chlamydia or gonorrhea infections Cocaine or opiate use Nightshift work in the past week

Sharkey JT, Puttaramu R, Word RA, Olcese J. Melatonin synergizes with oxytocin to enhance contractility of human myometrial smooth muscle cells. J Clin Endocrinol Metab. 2009 Feb;94(2):421-7. doi: 10.1210/jc.2008-1723. Epub 2008 Nov 11.

Olcese J, Beesley S. Clinical significance of melatonin receptors in the human myometrium. Fertil Steril. 2014 Aug;102(2):329-35. doi: 10.1016/j.fertnstert.2014.06.020. Epub 2014 Jul 9.

Olcese J, Lozier S, Paradise C. Melatonin and the circadian timing of human parturition. Reprod Sci. 2013 Feb;20(2):168-74. doi: 10.1177/1933719112442244. Epub 2012 May 3.

Sharkey JT, Cable C, Olcese J. Melatonin sensitizes human myometrial cells to oxytocin in a protein kinase C alpha/extracellular-signal regulated kinase-dependent manner. J Clin Endocrinol Metab. 2010 Jun;95(6):2902-8. doi: 10.1210/jc.2009-2137. Epub 2010 Apr 9.