T-helper 2-cytokine levels in women with threatened abortion Roberto Paradisi a,* , Mario Maldini-Casadei b , Paola Boni b , Paolo Busacchi a , Eleonora Porcu a , Stefano Venturoli a a Department of Obstetrics and Gynecology and Reproductive Biology, University Alma Mater Studiorum of Bologna, S. Orsola Hospital, Massarenti 13, Bologna 40138, Italy b Central Laboratory, S. Orsola Hospital, Bologna, Italy Received 30 April 2002; received in revised form 7 January 2003; accepted 29 January 2003 Abstract Objective: Considering that successful embryo development has been immunologically attributed to a T-helper 2 phenomenon and that threatened abortion is a very frequent but pathogenetically not well-defined clinical entity, our purpose was to investigate serum levels of the main T-helper 2-type cytokines during the evolution of this condition. Study design: Three T-helper 2-type cytokines (interleukin-6 (IL-6), interleukin-10 (IL-10), interleukin-13 (IL-13)) were measured by an enzyme-linked immunosorbent assay (ELISA) in serum of 12 women with threatened abortion both at hospital admission and discharge time. Fourteen women with missed abortion, 14 normal pregnant women and 14 normal non-pregnant women represent study control groups. Results: Serum concentrations of the selected T-helper 2-type cytokines showed no significant differences in women with threatened abortion with those of normal pregnant and non-pregnant women, whereas showed significantly lower values in women with missed abortion. Conclusion: Our data (a) confirm the concept that first-trimester normal pregnancy is a T-helper 2 phenomenon, (b) show that threatened abortion, when T-helper 2-biased, may tend to a positive evolution of the condition, (c) display that interleukin-10, particularly, may represent a useful diagnostic and prognostic marker for predicting the normal continuance of the pregnancy in threatened abortion, (d) confirm the existence of a T-helper 2-type pattern deficiency in missed abortion, and finally (e) may open the way to new T-helper 2-biased immune therapies in case of difficult first-trimester pregnancies. # 2003 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Cytokines; Interleukin-6; Interleukin-10; Interleukin-13; Threatened abortion 1. Introduction In spite of theworld population explosion in the last century the process leading human pregnancy is fairly inefficient because 70% of conceptions fail to achieve viability. Sponta- neous abortion is the most common complication of preg- nancy and is classically defined as a clinically recognized pregnancy loss before 20 weeks’ gestation and occurs at a frequency of 15% [1]. While recurrent spontaneous abortion has been extensively studied [1,2], sporadic spontaneous abortion and, in particular, the first step of this pathological condition, the threatened abortion, has been characterized to a lesser extent. Threatened abortion refers to an intrauterine viable clinical pregnancy accompanied by an intrauterine source of painless vaginal bleeding. A subchorionic hematoma caused by partial placental abruption is often the source of bleeding but not necessarily associated with ultimate pregnancy loss [3]. Threatened abortion, in fact, may settle with normal con- tinuation of the pregnancy or progress and be accompanied by pain to become an inevitable abortion. To day, do not exist specific markers that can help to predict if pregnancy continues developing until delivery or terminates in abor- tion. Signs and symptoms of pregnancy, such as nausea, vomiting, tiredness, breast tenderness may be present in both conditions, so the clinical assessment of threatened abortion is unreliable in most cases and should be superseded by ready access to sonographic assessment [4]. Even though pelvic examination and sonographic scan may usually lead to a proper diagnosis, the use of transvaginal color Doppler ultrasound is not helpful for predicting positive pregnancy outcome in threatened abortion because no apparent circu- latory alteration occurs [5], excluding a vascular pathogen- esis. Doubling of b-hCG subunit levels every 48–72 h is often but not always diagnostically useful [6], limiting the importance of endocrine factors in threatened abortion. No specific infection has been identified as primary cause of abortion, moreover infections have occurred in women with successful pregnancy at the same rate as those experiencing European Journal of Obstetrics & Gynecology and Reproductive Biology 111 (2003) 43–49 * Corresponding author. Tel.: þ39-051-6363494; fax: þ39-051-301994. E-mail address: paradisi@med.unibo.it (R. Paradisi). 0301-2115/$ – see front matter # 2003 Elsevier Science Ireland Ltd. All rights reserved. doi:10.1016/S0301-2115(03)00119-2