ER Map® es un nuevo test personalizado que permite determinar el estado de receptividad del endometrio durante la ventana de implantación (VI). ER Map® identifica el mejor momento del endometrio para la transferencia del embrión, aumentando la probabilidad de implantación y embarazo. ER Map® es una herramienta molecular que analiza la expresión génica de 48 genes involucrados en el desarrollo de la receptividad endometrial y la respuesta inmune materna asociada a la implantación embrionaria.
El test ER Map® permite  identificar el momento  óptimo del endometrio  para transferir el embrión  exactamente cuando hay  más probabilidades de  embarazo

ER Map®

Endometrial Receptivity Map

ER Map® nxt is a molecular tool that analyses the expression of genes with functional relevance in the process of endometrial receptivity.

The endometrium is refractory to pregnancy at other times of the menstrual cycle, outside the Implantation Window (IW).

Recent studies have shown that the profile of endometrial receptivity during the window of implantation and its transcriptomic signature could be used to assess endometrial function1.

ENAC | Accreditation Nº 1497/LE2766

In accordance with the requirements of the UNE-EN ISO 15189 standard, for the activities defined in the corresponding technical annex*.

IGLS acredita sus servicios bajo la norma ISO 15189


In short, the ER Map® test makes it possible to identify the optimal time for the endometrium to transfer the embryo, in other words, to define exactly when pregnancy is most likely to occur.

Biopsy of endometrial tissue
P+5.5 / LH+7

Introduction in the
ER Map® cryotube

Refrigeration at 4ºC
(at least 4 hours)

Sample shipment at
room temperature

Analysis of gene

Results in 10
working days


In short, the ER Map® test makes it possible to identify the optimal time for the endometrium to transfer the embryo, in other words, to define exactly when pregnancy is most likely to occur.

Identify your best moment


Add quality and confidence to your assisted reproduction treatment: go one step further and include the ER Map® test in your process. 


Tell your gynaecologist, he or she will show you how ER Map® can make a difference.


Your doctor will find the right option for you.


Your doctor will take care of everything so that we can continue to look after you as you deserve in your journey towards motherhood.

What is endometrial receptivity?

The endometrium is the tissue that lines the inside of the uterus and prepares each month for embryo implantation.

It is a very active structure, which undergoes periodic changes during the menstrual cycle and reaches an optimal receptive state for embryo implantation around days 19-21 of the menstrual cycle.

This period of time when the endometrium is receptive is called the “window of implantation” and occurs, in most women, 7 days after the endogenous LH peak (LH+7).

Multiple studies indicate that in many women this window may be displaced. Alterations in endometrial receptivity may be the cause of some cases of implantation failure or even recurrent miscarriages.

What is ER Map® used for?

ER Map® can characterise a patient’s endometrial receptivity status and determine whether or not the endometrium is receptive at the time of biopsy1 .

This test accurately detects the window of implantation and allows the embryo transfer to be programmed in a personalised way at the moment of maximum endometrial receptivity, increasing the probability of success of the assisted reproduction treatment2.

Who can benefit from ER Map®?

All patients undergoing assisted reproductive treatment can benefit from accurate determination of the window of implantation.

Approximately 30% of patients have a displaced VI2.

This test can be very useful even in patients with no apparent endometrial problems, normal uterus and endometrial thickness. ER Map® is especially recommended for couples who have experienced failed cycles or pregnancy loss after transfer of good quality embryos.

Why use ER Map®?

Traditional methods of endometrial assessment have been shown over the years to be insufficiently predictive and inaccurate in reliably determining the best time for the endometrium to receive the embryo.

Molecular diagnosis of endometrial status using ER Map® is an accurate technique capable of specifically determining the day on which the endometrium has reached the optimal stage for embryo implantation.

ER Map® is one of the most detailed and reliable tests currently available for the assessment of endometrial receptivity.

This study can be performed independently or in combination with other tests that, depending on the particular case and the medical history of each patient, the gynaecologist may prescribe in order to increase the chances of pregnancy:

ER Map® + Im Map® Pack Add to your endometrial receptivity study valuable information about the maternal immune response associated with embryonic implantation.

ER Map® + MicroBioMap® Pack Complete your endometrial receptivity study with an analysis of the endometrial microbiota, which examines the presence of 18 pathogenic microorganisms responsible for chronic endometritis and 4 species of Lactobacillus in the endometrium. This pack is especially recommended for patients with implantation failures, recurrent miscarriages and/or suspicion of chronic endometritis.

ER Map® + MicroBioMap® + Im Map® Pack A comprehensive study of the uterine environment that provides your gynaecologist with a 360-degree view, including the implantation window, analysis of the endometrial microbiota, and activity levels of the immune cell populations. Based on the results, our specialists will be able to recommend to the patient the most suitable therapies or treatments not only to achieve the much-desired pregnancy but also to reduce the likelihood of complications during the gestation process.

Reproductive outcomes of patients afer the first single embryo transfer following ER Map.
Positive B-hCG rates (green bars) and clinical pregnancy rates (grey bars) comparison between the group of patients that followed ER Map progesterone pretreatment and those that deviated more than 12h from this recommendation.
Diagnóstico avanzado de infertilidad masculina

1. Enciso M. et al.Hum Reprod 2018; 33(2): 220-228.

2. Enciso M. et al.Sci Rep 2021; 11(1): 1-8

3. Enciso M. et al. Scientific Reports 2021