Neonatal Uterine Bleedings: An Ignored Sign but a Possible Cause of Early-Onset Endometriosis - A Systematic Review.

Objective: Based on the hypothesis that neonatal uterine bleedings (NUB), occurring mostly in the first week after birth, could represent a pathogenetic mechanism for early-onset endometriosis, this systematic review (SR) was undertaken to evaluate the prevalence and screening strategies used to assess and quantify NUB.

Design: Both a SR and a sample literature search in PubMed and Embase were conducted to gather information on NUB prevalence and screening techniques. This was performed by an information specialist.

The development of the human uterus: morphogenesis to menarche.

There is emerging evidence that early uterine development in humans is an important determinant of conditions such as ontogenetic progesterone resistance, menstrual preconditioning, defective deep placentation and pre-eclampsia in young adolescents. A key observation is the relative infrequency of neonatal uterine bleeding and hormone withdrawal at birth. The origin of the uterus from the fusion of the two paramesonephric, or Müllerian, ducts was described almost 200 years ago.

Effects of progestin-only contraceptives on the endometrium.

Introduction: The contraceptive activity of synthetic progestins is mediated through three basic mechanisms: (a) An anti-gonadotrophic action leading to the inhibition of ovulation; (b) Changes in cervical mucus characteristics that inhibit sperm penetration and (c) desynchronization of the endometrial picture necessary for implantation.

Areas Covered: Mechanisms involved in the progestin-induced endometrium desynchronization are individually reviewed for each of the routes of administration and, whenever possible, by individual members of the various families of synthetic progestin derivatives.

Expert Opinion: For contraceptive purposes, progestins are today administered through several routes: orally, as injections, subdermally and via the vagina or the uterine cavity.

Acute atherosis and diffuse lipid infiltration of the placental bed: A review of historical lipid studies.

Based on a variety of tissue samples, including Caesarean hysterectomy specimens with the placenta in situ, a detailed map of uteroplacental vascular lesions was established in over a century of research. One such lesion is acute atherosis of unremodelled basal and uteroplacental arteries, defined by the presence of fibrinoid necrosis, subendothelial macrophage foam cells, and perivascular lymphocytic infiltration. Two studies conducted over 50 years ago used Oil Red O staining of frozen tissue sections to visualise lipid infiltration of placental bed vessels and document the presence of lipid-laden foam cells in acute atherosis.