Although Caesarean section (CS) is often a necessary surgical intervention, it may also be associated with an increased risk of short- and long-term sequelae. It was thought that CS may increase the risk of female subfertility or even infertility. In assisted reproductive technology (ART) cycles, the process of implantation is believed to be the most important factor in determining pregnancy outcome. In view of conflicting results on the influence of a previous CS on outcomes of ART, this study will be conducted to investigate the impact of the mode of previous delivery on ICSI outcomes.

The use of CS has steadily increased worldwide and will continue increasing over the current decade where both unmet need and overuse are expected to coexist. The medical field now acknowledges a patient's right to actively participate in her choice of medical treatments, including the method of delivery what is known as CS on demand, a primary CS performed on the mother's request without any recognized medical or obstetric Indications that may also increase the rate of C.S. Although CS is often a necessary surgical intervention, it may also be associated with an increased risk of short- and long-term sequelae eg. infection, haemorrhage and increased risk of several obstetric complications in subsequent pregnancies, including mal-placentation, Caesarean scar pregnancies, morbidly adherent placentae and uterine rupture. It was thought that CS may increase the risk of female subfertility or even infertility. The possible reasons for this impact on fertility may be related to infections, adhesions formation, placental bed disruption or other non-medical factors (age, culture, education). Different mechanisms were hypothesized to explain the detrimental uterine environment associated with the presence of CS niche, that may lead to subfertility including accumulation of intrauterine fluid, altered immunobiology, increased inflammation, distorted contractility of the uterus caused by fibrosis or interruption of the myometrial layer at the site of the niche. In ART cycles, the process of implantation is believed to be the most important factor in determining pregnancy outcome, because the embryos are directly transferred into the uterine cavity and so the tubal factor can be excluded. To date, knowledge on the influence of a previous CS on outcomes of ART is limited with different conclusions in terms of live birth, miscarriage and implantation rates. In view of these conflicting results, more adequately powered studies are warranted. Therefore, this study will be conducted to investigate the impact of the mode of previous delivery on ICSI outcomes.

Inclusion Criteria:

• Patient age 20-35years.
• BMI 18- 30.
• Women with some indications for freeze all technique as patients with high risk for developing ovarian hyperstimulation syndrome (OHSS), patients with treatable tubal or uterine anomalies that were discovered during controlled ovarian hyperstimulation (COH) or in patients with elevated serum progesterone levels

Exclusion Criteria:

• Severe form of endometriosis.
• Congenital uterine anomalies.
• Scarred uterus due to previous myomectomy.
• Women diagnosed with moderate to severe degrees of intrauterine adhesions.
• Women with fibroid uteri.
• Patients with bad quality embryos.
• Untreated hydrosalpinges.
• All fresh transfer cycles will be excluded.

Women complaining of secondary infertility, whether delivered vaginally or by one previous C.S, who will undergo ICSI in the IVF private centers